As modern society infrastructure and various operations (e.g., civilian, military) increasingly come to depend on ubiquitous always-on information system connectivity and intelligence antennas have an important role to play in addressing such issues.
Low earth orbiting satellites provide a means for maintaining connections to information systems. Low earth orbiting satellites move relatively rapidly from one horizon to the opposite horizon as viewed from a terrestrial observation point. To maintain connectivity with such satellites, it would be desirable to have antenna systems that can sustain communications over a wide range of polar angles. There are mechanically steered antenna systems that track satellites, but these suffer certain disadvantages such as size and weight, mechanical wear and inability to switch from pointing from one target (e.g., satellite) to another in millisecond or less periods, so as to maintain communications when one satellite passes beyond the horizon.
Additionally it would be desirable to have a single antenna system that can operate with either Left Hand Circularly Polarized (LHCP) radio waves or Right Hand Circularly Polarized (RHCP) radio waves, so that communications can be maintained in either case without the provision of two separate antenna systems, which would add bulk and cost which is undesirable.
There are certain phased array patch antenna systems that are capable of both LHCP and RHCP operation but unfortunately the gain pattern of such patch antennas is weak at high polar angles, so maintaining communication with satellites near the horizon is problematic.
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